The objective of this study was to assess the chemical characteristics of cold-pressed beech nut oil. The nuts, gathered from the forest, comprised 25.35% water, 13.19% oil, and 19.40% protein. The ...predominant fatty acid was linoleic acid (40.5%), followed by oleic acid (35.0%) and gondoic acid (7.7%). All four tocopherols were present in the oil, with γ-tocopherol being the dominant form at 99.38 mg per 100 g of oil. The total sterol content was 2708.73 mg per kg of oil, with β-sitosterol constituting 80.5% of all sterols. The main characteristics of the oil included its relatively high tocopherol and gondoic acid content, a dominant oleic–linoleic fatty acid profile, and elevated levels of carotenoids.
The aim of this study was to determine the effects of seeding density on the seed yield of white mustard, the oil yield and fatty acid composition under the agroecological conditions of the ...northwestern Republic of Croatia. The field trials were conducted at the experimental station of the Faculty of Agriculture, University of Zagreb (45° 48’ N, 16° 05’ E) during two growing seasons. The trial included four seeding densities of white mustard: 50, 70, 90 and 110 germinable seeds m-2. The trial was set up using a randomized block design with five replications. The highest seed yield was obtained with a seeding density of 110 germinable seeds m-2, with no significant differences between seeding rates of 70 and 90 germinable seeds m-2. The average oil content during researched years varied from 23.97 % in the seeding density of 50 germinable seeds m-2 to 24.37 % in the seeding density of 90 germinable seeds m-2. The higher oil yield was achieved in 2014 due to the higher oil content in the seed that year. Regarding fatty acid composition, erucic acid was dominant along with oleic acid, linoleic acid, and linolenic acid.
Namen raziskave je bil določiti vpliv gostote setve na pridelk olja in semena ter sestavo maščobnih kislin bele gorjušice v agroekoloških razmerah severozahodne Hrvaške. Poljski poskus je potekal na poskusni postaji Agronomske fakultete Univerze v Zagrebu (45° 48’ N, 16° 05’ E) v dveh rastnih sezonah. Poskus je obsegal štiri gostote semen bele gorjušice in sicer 50, 70, 90 in 110 kaljivih semen m-2. Poskus je bilo zasnovan kot naključni bločni poskus s petimi ponovitvami. Največji pridelek semen je bil dosežen z gostoto setve 110 kaljivih semen m-2, vendar brez značilnih razlik z gostotama setve 70 in 90 kaljivih semen m-2. Poprečna vsebnost olja je v letih poskusa variirala od 23,97 % pri gostoti setve 50 kaljivih semen m-2 do 24,37 % pri gostoti setve 90 kaljivih semen m-2. Največja vsebnost olja je bila dosežena v letu 2014 zaradi nasplošno največje vsebnosti olja v tem letu. Glede sestave maščobnih kislin je bila dominantna erucična kislina, ki so ji sledile oleinska, linoleična in linolenska kislina.
•Profile of nettle root extracts with 10 detected sterols.•Profile of nettle root extracts with 3 detected pentacyclic terpenes.•Nettle root sterols and pentacyclic terpenes differ significantly upon ...climate.
Nettle (Urtica dioica L.) root is a well-known source of valuable phytosterols, however scientific data regarding their composition are scarce. Therefore, this study aimed to examine the profile of phytosterols and triterpenes in nettle root (12 samples) harvested in three different climate regions and to provide more detailed information on the profile of nettle root lipophilic extract. Nettle root samples were extracted using n-hexane, while detection and quantification of phytosterols and triterpenes was achieved by GC–MS. Average content of total sterols was 0.80–0.86 g kg−1 dry weight and total pentacyclic triterpenes (PT) of 0.0048–0.0070 g kg−1. A total of 10 sterols and 3 PT were detected. The dominant sterol in all samples was β-sitosterol, followed by campesterol and stigmasterol. Lower quantities of Δ7 sterol - citrostadienol were detected. The dominant PT in root samples from warmer regions was β-amyrin acetate, while samples from the colder region showed the predominance of β-amyrin.
Rehydration of food products was carried out in various amounts of liquid. The effects of the solid-to-liquid ratio on rehydration characteristics of dried red beets were investigated. Six values of ...the solid-to-liquid ratio (1:20, 1:15, 1:10, 1:5, 1:3, and 1:1) were taken into consideration. Red beets cubes (10 mm) were dried in a forced convection (2 m/s; 60 °C) and then rehydrated in distilled water at a temperature of 20 °C. The kinetics of mass gain, dry matter loss, water gain, moisture content increase, and volume increase were modeled using the empirical Peleg model which parameters have physical meanings. Equations were formulated to make the Peleg model parameters dependent on the solid-to-liquid ratio. The obtained results indicated that the amount of rehydrating water influenced the values of the model parameters and the course of dried red beets rehydration and helped explain the rehydration kinetics. The Peleg model can be recommended for describing the kinetics of mass gain (R2 = 0.9662–0.9895), dry matter loss (R2 = 0.7042–0.9881), water gain (R2 = 0.9732–0.9913), moisture content increase (R2 = 0.9770–0.9929), and volume increase (R2 = 0.9374–0.9847) during the rehydration of dried red beet cubes at all considered values of the solid-to-liquid ratio.
Some dehydrated products must be rehydrated before consumption or further industry processing. Optimization of the rehydration process needs mathematical models of the process. Despite the widespread ...use of computers and their associated software, empirical equations are still widely used in view of their simplicity and ease of computation. The mathematical description of the kinetics of mass gain, volume increase, dry matter loss, and moisture content increase and changes of rehydration indices during the rehydration of dried red beets was investigated. The effects of drying air temperature (Td), drying air velocity (vd), characteristic dimension (L), and rehydration temperature (Tr) on model constants were also examined. Red beets cubes (10 mm) and slices (5 and 10 mm) were dried in natural convection (vd = 0.01 m/s), forced convection (vd = 2 m/s), and fluidization (vd = 6 m/s) at Td = 50, 60, and 70 °C. The rehydration was conducted in distilled water at Tr = 20, 45, and 70 °C. The kinetics of rehydrating dried red beets was modelled applying five empirical models: Peleg, Lewis (Newton), Henderson–Pabis, Page, and modified Page. Equations were developed to make the model constants dependent on Td, vd, L, and Tr. Artificial neural networks (ANNs) (feedforward multilayer perceptron) were adopted to condition the rehydration indices on Td, vd, L, and Tr. The following models can be recommended as the most acceptable: (1) the modified Page model for mass gain (RMSE = 0.0236–0.0897) and for volume increase (RMSE = 0.0213–0.0972), (2) the Peleg model for dry mass loss (RMSE = 0.0161–0.610), and (3) the Henderson–Pabis model for moisture content increase (RMSE = 0.0350–0.1062). The ANNs performed the rehydration indices in an acceptable way (RMSE = 0.0528–0.2285). Both the rehydration indices and model constants depended (but to a different degree) on the investigated drying and rehydration conditions.
Heating the rapeseed prior to the oil extraction is conducted to increase the oil yield but it can also induce changes of various components of the seed. These changes may affect the composition of ...the volatile and non-volatile compounds of produced virgin rapeseed oil. The aim of our study is to determine the impact of different conditioning temperatures (60, 80 and 100degreesC) on the quality, nutritional value, aroma profile and sensory characteristics of virgin rapeseed oil. Conditioning the seeds at all three temperatures had no influence on the quality and major nutritional components (fatty acids and tocopherols) of the produced oil. However, temperature increase caused an exponential increase of canolol and significant changes in the aroma and sensory profile of the produced oil samples. The dominant volatile compounds of cold-pressed and virgin oil produced at 60 degreesC were enzymatic degradation products of glucosinolates (isothiocyanates and epithionitriles), responsible for pronounced seed-like flavour of these types of oil. Increasing production temperature deactivated enzymes and caused thermal decomposition of seed components and increment of nitriles, aldehydes, pyrazines and furanes, carriers of nutty and roasty flavour. These results can help producers to design virgin rapeseed oil with specific and desirable sensory characteristics.Key words: rapeseed oil, seed conditioning, nutritional value, volatile components, sensory analysis
Plant proteins are receiving a lot of attention due to their abundance in nature, customizable properties, biodegradability, biocompatibility, and bioactivity. As a result of global sustainability ...concerns, the availability of novel plant protein sources is rapidly growing, while the extensively studied ones are derived from byproducts of major agro-industrial crops. Owing to their beneficial properties, a significant effort is being made to investigate plant proteins' application in biomedicine, such as making fibrous materials for wound healing, controlled drug release, and tissue regeneration. Electrospinning technology is a versatile platform for creating nanofibrous materials fabricated from biopolymers that can be modified and functionalized for various purposes. This review focuses on recent advancements and promising directions for further research of an electrospun plant protein-based system. The article highlights examples of zein, soy, and wheat proteins to illustrate their electrospinning feasibility and biomedical potential. Similar assessments with proteins from less-represented plant sources, such as canola, pea, taro, and amaranth, are also described.
The aim of the present study was to examine changes in phenolic compounds during refining of rapeseed oil. In crude rapeseed oil, 4-vinylsyringol (canolol) is the dominant phenolic compound, ...accounting for 85% of total phenolics. Refining decreased the total amount of phenolic compounds by 90%. NMR and MS analyses of edible rapeseed oil phenolic extracts identified 4-vinylsyringol dimer as the dominant phenolic compound. This phenolic compound appears to form through acid-catalyzed dimerization-aromatic substitution of 4-vinylsyringol monomers. Analysis of rapeseed oils from different stages of the refining process suggest that 4-vinylsyringol dimer forms during the neutralization phase, when H3PO4 acts as a catalyst, or during bleaching, when acid-activated bleaching earth acts as the catalyst. Whether 4-vinylsyringol forms during one or the other phase appears to depend on the phospholipid content of the crude oil. These insights may be useful for designing rapeseed oil refining processes that maximize levels of 4-vinylsyringol dimer.
Because of its high market value, pumpkin seed oil is occasionally adulterated by cheaper refined oils, usually sunflower oil. The standard method for detecting its authenticity is based on expensive ...and laborious determination of the sterol composition. Therefore, the objective of this study was to determine the sterol content and authenticity of retail oils labelled as pumpkin seed oil and also to investigate the potential of near-infrared spectroscopy (NIR) and colourimetry in detecting adulteration. The results show that due to the significant decrease in Δ7-sterols and increase in Δ5-sterols, 48% of the analysed oils can be declared as adulterated blends of pumpkin seed and sunflower oil. Significant differences in NIR spectroscopy data, in the range of 904-922 nm and 1675-1699 nm, and colourimetric data were found between the control pumpkin seed oil and sunflower oil, but only the NIR method had the potential to detect the authenticity of pumpkin seed oil, which was confirmed by principal component analysis. Orthogonal projection on latent structures (OPLS) discriminant analysis, resulted in working classification models that were able to discriminate pure and adulterated oil. OPLS models based on NIR spectra were also able to successfully predict the content of β-sitosterol and Δ7,22-stigmastadienol in the analysed oils.
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